Inelastic neutron scattering study of undeuterated [Mn9O7(OAc)11(thme)(py)3(H2O)2]

We report on the magnetic properties of the enneanuclear mixed-valent single-molecule magnet [Mn9O7(OAc)11(thme)(py)3(H2O)2] (1). Using inelastic neutron scattering (INS) spectroscopy, we have confirmed the S = 17/2 cluster ground state of 1. Furthermore, we have determined accurately the anisotropy parameters of the zero field split ground state. The cluster 1 exhibits a strong negative axial anisotropy D[Sˆz2-S(S+1)/3] where D = −0.249(5) cm−1. It is necessary to include an axial higher order term (B40) in the effective spin Hamiltonian to account for the experimental data.

Inelastic neutron scattering spectra of the title compound have been measured at λ = 6.5 Å and T = 1.6 and 12 K, respectively. The peaks observed in this figure enabled accurate determination of the zero field splitting parameters of this single molecule magnet.Figure optionsDownload as PowerPoint slide